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round the stem, become folded lengthways or conduplicate. They are clothed with long, sparse hairs, and show a few teeth, or rather knobs, along the edge, one terminating each of the veins, which are thicker than in subsequent stages (fig. 63). The teeth, or

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AUCUBA JAPONICA. Highly magnified.

FIG. 59, first pair of leaves, front view; FIG. 60, ditto, side view; FIG. 61, second pair; FIG. 62, ditto, more developed; FIG. 63, third pair.

knobs, are also much larger in proportion than in the full-grown leaf.

COMMON LAUREL

The subjoined figures illustrate the structure of the bud of a Common Laurel (Cerasus Laurocerasus).

Here again the leaf commences as a small projection or lobe immediately below the growing-point. Very soon

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FIGS. 64-70, leaves and their stipules; s, s, stipules; x 10.
FIGS. 71-79, outer scales.

two other lobes appear at the base of the first (fig. 64, s,s).

These are the stipules.

They are at first much smaller

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than the leaf. By the time, however, that the leaf-blade has reached th inch (fig. 67) the stipules have caught it up. They are more oval, more pointed, and bordered by a row of small projections. They continue to grow (fig. 68) more rapidly than the leaf-blade, and somewhat unequally (fig. 69), the larger one becoming rather more (fig. 70), the shorter one rather less, than double as long as the leaf-blade. Then comes a somewhat abrupt transition, and the outer scales do not, of course, correspond to stages in the development of a normal leaf. A rudimentary leaf, such as that in fig. 70, is followed by a scale of quite a different form: broader, wrapping round the bud, and consisting of three parts nearly but not quite equal in length, and separated almost to the base (fig. 71); the two outer pieces representing the stipules are rather broader than the central. In the next (fig. 72) the leaf-blade is rather longer than the stipules, and the common stalk or leaf-base is longer in proportion. This is still more the case in the next two (figs. 73, 74). In the twelfth (fig. 75) the leaf-stalk is abruptly truncated; and in the following the stalk and stipules are reduced to three small prominences. Finally, the outer scale is much shorter and broader in proportion (fig. 79).

THE TULIP TREE (Liriodendron tulipifera)

In the Tulip Tree the leaf commences as a slight projection immediately below the growing-point, and

gradually widens into a ridge, the two ends of which eventually meet, forming a ring.

One part raises itself above the rest and forms the leaf-stalk; the two side pieces become the stipules. They grow upwards and inwards, finally forming a hood over the growing-point. About the time when

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TULIP TREE (Liriodendron tulipifera).

FIG. 80.-Very young leaf and stipule, x 20. FIG. 81.-Do. do. second stage, x 20. FIG. 82.-Do. do. rather more advanced stage, × 20.

the stipules meet the leaf-blade commences. It is at first a very narrow, delicate, hyaline membrane. The bud then assumes the appearance shown in fig. 80.

The next stage (fig. 81) shows the growth of the leaf-blade, which is more developed in fig. 82. Fig. 17, p. 14, shows how closely the young leaf fits in the

hollow of the bud; while the final arrangement of the leaf in the bud is shown in figs. 17 and 18.

In the axillary buds, as a rule, the outer covering consists of two stipules, the rest of the leaf not being developed (fig. 83). Sometimes, however, at the base a small projection may be seen (fig. 84), which is a

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83

84

FIGS. 83-86.-TULIP TREE.

85

86

Outlines of different axillary buds.

rudiment of a petiole. Sometimes this is rather more developed (fig. 85), and sometimes a rudimentary blade also appears (fig. 86).

The reversal of the leaf in the bud, owing to the length and early development of the petiole, is very unusual. In Amicia Zygomeris the leaf is bent, but only forms a right angle with the petiole.

ROSE

The leaf of the Rose (see ante, fig. 58, p. 46) is more complicated. It commences as a small knob at the side of, and immediately below, the growing-point. When this knob has reached a certain length it presents two lobes (fig. 87), which arise almost simultaneously. The upper of these becomes one of the

1 According to Schacht, however, the stipule appears first.

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